The present invention relates to a gyroscopic instrument, more particularly to a gyroscopic compass of the type in which an inner container enclosing one or more high speed rotating gyro rotors is floating in a supporting liquid filled in an outer container, with the inner container being supplied with electric power from the outer container side. Specifically, the invention relates to a gyroscopic instrument in which an inner container is supported to float by a magnetic fluid free of contact with an outer container.
Gyroscopic instruments of this type are well known in the art and are disclosed, for instance, in U.S. Pat. Nos. 3,373,617 and 4,008,623. A prior art gyroscopic instrument is shown in FIG. 1. A hollow sphere 1 contains a pair of motordriven gyroscopes therein and is provided with conductive electrode postions 2 and 3 at its poles and with an electrode portion 4 extending along its equator. The sphere is kept in a freely floating condition within an electrically conductive liquid. Electrodes 5, 6 and 7 are provided on a vessel surrounding the sphere at a distance therefrom. The vessel consists of a lower, substantially semi-spherical part 8 and of a coaxial upper dish-shaped part 9. The parts 8 and 9 of the vessel are mounted on the inside of and rigidly connected with a spherical container 10. The container is filled with the electrically conductive liquid and is mounted in a housing (not shown). A pump 11 is mounted on the container 10. An inlet is formed by an aperture 12 of the vessel at the bottom thereof whereas an outlet is formed by the space provided between the upper edge of the vessel part 8 and the edge of the dish-shaped vessel part 9. A gap 13 is formed between the lower part of the sphere 1 and the semi-spherical part 8. The inner surface 14 of the container 10 and the outer surface of the vessel part 8 confine between them the passageway leading from the outlet to the inlet 12. The flow of liquid entering the gap 13 through the inlet aperture 12 will flow in all directions as indicated by the arrows 15, thereby forming a liquid bearing which will keep the sphere 1 in a freely floating condition centered in the spherical vessel 8, 9.
As is easily understood, the prior art gyroscopic instrument has such drawbacks as follows: (1) a pump is required to be mounted on an outer container in order to produce the flow of a liquid for holding an inner container, (2) the inner surface of an outer container must be shaped to induce sufficient restoring forces to act upon an inner container from various directions, (3) a control system is further required for maintaining the temperature of the supporting liquid constant, and (4) an inner container may be damaged due to, for instance, the pitching and rolling of the ship, when the gyroscopic instrument is switched off, since the inner container descends and stays on the bottom inner surface of an outer container.
Accordingly, an object of the present invention is to provide a gyroscopic instrument which does not require a pump for producing the flow of a supporting liquid, with the inner surface of the outer container thereof being simply shaped.
Another object of the invention is to provide a gyroscopic instrument which does not require a control system for maintaining the temperature of a supporting liquid constant.
Another object of the invention is to provide a gyroscopic instrument which is capable of floating the inner container even when the instrument is switched off.
Another object of the invention is to provide a gyroscopic instrument in which the inner container is supported to float by the magnetic fluid subjected to magnetic fields.
Another object of the invention is to provide a gyroscopic instrument in which the magnetic fields are locally generated by the magnets mounted on the inner and/or outer containers at a plurality of places.
Another object of the invention is to provide a gyroscopic instrument in which the magnetic fluid regions influenced by the magnetic fields generated can be narrowed so that the mechanical and electrical operations taking place in the inner container are not affected by the magnetic fields.